In order to increase the efficiency of data transmission when acquiring data and transmitting the acquired data to a terminal, a technique that compresses the data to reduce the amount of data and transmits the compressed data is used. For example, image data is acquired from a device such as a camera, and the image data is compressed and transmitted to a terminal. An example of application of this technique is displaying an image taken by an in-vehicle camera such as a back monitor or a top view monitor of an automobile or the like on a display or the like. In such a technique, it is necessary to reduce a time lag between the timing when an image is captured by the camera and the timing when the image is displayed on the display (to reduce latency). In this case, it is possible to increase the transmission speed from the camera to the display by compressing and transmitting the image data from the camera.
In relation to the above technique, Patent Literature 1 discloses an image transmission device that can transmit image data to a network and store the image data in HDD at the same time by an encoding circuit and a compression means in a single system. Because the technique disclosed in Patent Literature 1 sorts the compressed data in order of compression and stores them in a compressed data storage means, and then reads the compressed data from the compressed data storage means in response to a request from a terminal, it is possible to transmit individual compressed data to each terminal.